1. Field of the Invention
The present invention relates to electrical trainline junction boxes and, more specifically, to junction box that is more easily wired into a trainline.
2. Description of the Related Art
A train line junction box assembly is generally provided at each end of the rail car or locomotive. An electrical cable line within the car is typically connected at a terminal block within the junction box. An electrical connector receptacle is also provided in the junction box and connected to the terminal block. The cable is then received in the connector/receptacle to interconnect between a pair of cars. Electronically controlled pneumatic (ECP) train brakes generally use a junction box for trainline power termination and another, more specialized junction box that houses the electronic identification modules that provides vehicle specific information to the car control device or trainline communication center, such as vehicle number, type of vehicle, weight, and other vehicle parameters.
A electronic identification junction box typically includes a housing and a terminal block which is mounted in the interior of the housing. Fastener apertures that are provided adjacent to the corners of the walls of the housing allow for fasteners that mount the body of the housing to the car. A strain relief sleeve member is threadably received on a threaded sleeve and includes a split collar that is tightened by a screw. A cable containing the trainline wires is received through the strain relief member and the internal wires are connected to the terminal block. Unfortunately, the walls of the housing are relatively thin and the threading can only engage the housing with one or two turns. As a result, the interconnection is weak and vulnerable to damage and seepage, which prevents the moisture tightness of the enclosure for the junction box.
More recent junction boxes for use in ECP trains, such as that is described in U.S. Pat. No. 6,669,506, remain susceptible to damage. Trainline junction boxes, which must be wired in the field by highly trained personnel, are susceptible to installation or wiring mistakes that expose the sensitive internal components to detrimental environmental conditions. Thus, there is a need for an identification module junction box that is more robust and that preferably reduces the possibility for installation and wiring mistakes. For example, existing junction boxes require that the installer open the cover of the junction box and make the right connections between the ring terminals on the trainline cables and the threaded posts on the IDM.
This presents several risks and difficulties, including making the right connections, properly installing the ring terminal and associated flat washer, lock washer, and nut on the terminal post, properly torquing the small ring terminal nuts, properly replacing the junction box cover and cover gasket, and properly torquing the cover bolts. Failure to properly do this assembly onto the rail car could result in system failure due to water ingress, a wire loosening from the terminal stud, or miswiring. In addition, there is a potential safety risk to the installer/maintainer if the system power was not shut off prior to removing the junction box cover.